The present invention relates to maintenance of compatibility in an IC card and its function expansion, and to, for example, a technology effective for application to an IC card for implementing a multibank or a multifunction while compatibility with a multimedia card being maintained.
With a view toward executing transmission of information between a cellular phone and a digital network device, or the like, a memory card like a multimedia card has been proposed which has implemented a reduction in size and weight and simplification of an interface. As described in, for example, the Interface (December issue in 1999) issued by CQ Publishing Co., Ltd., a multimedia card has seven connector terminals as external interface terminals and adopts a serial interface. This is capable of reducing a load on a host system as compared with an ATA interface adopted by a PC card or hard disk and is available even for a simpler system. Further, the same reference has also described that an SD card has been proposed as an upper compatible memory card of the multimedia card.
The present inventors have discussed a function expansion of a storage-system IC card such as a multimedia card or the like. Thus, the present inventors have previously filed the invention wherein extension terminals are provided while compatibility is being maintained with respect to a standardized terminal array of a multimedia card or the like, thereby enabling a function expansion such as an increase in the number of data bits (Unexamined Patent Application No. 2000-18030). Further, the present inventors have carried out discussions directed toward the implementation of a multibank or multifunction using such extension terminals. In a GSM (Group Special Mobile) mobile communication system or the like using an SIM (Subscriber Identity Module) of an IC card, for example, an SIM card has a single chip microcomputer or the like, which stores subscriber information and account information or the like necessary for subscriber acknowledgement and management for security and realizes communication protocols, and which builds therein a nonvolatile memory such as a flash memory, for example. When one attempts to apply a storage card such as a multimedia card to a cellular phone of such a GSM mobile communication system, an insertion slot for the storage card is required in addition to one for the SIM card. Thus, the present inventors have found that there is room for improvements in terms of space factors. Further, the present inventors have found that a difference in security level unavoidably occurs in memory information between the storage card and the SIM card and hence there is a necessity that the difference in security level is allowable as a difference upon the multifunction.
An object of the present invention is to provide an IC card capable of executing a function expansion such as a multibank or multifunction or the like while compatibility with a predetermined standard is being maintained with respect to a terminal array.
Another object of the present invention is to provide an IC card capable of expanding multifunctions different in security level.
The above, other objects and novel features of the present invention will become apparent from the following description of the present specification and the accompanying drawings.
[1] An IC card according to the present invention takes into consideration compatibility and a function expansion thereof. As to the compatibility of the IC card, upward compatibility and downward compatibility are maintained. The upward compatibility is that a downward IC card can be used by being inserted into a card slot of an upward IC card, for example. The downward compatibility is that the IC card can be used by being inserted into a card slot of the downward IC card, for example. An IC card has a first functional block and a second functional block each comprising a semiconductor integrated circuit and has a configuration wherein a plurality of connector terminals are exposed.
In terms of the compatibility of the IC card, the plurality of connector terminals are disposed in plural rows in a zigzag fashion between columns adjacent to one another back and forth as viewed in an insertion direction of the IC card. If an expression different from one for the zigzag placement thereof is taken, then the plurality of connector terminals have an array of two columns formed back and forth as viewed in an IC card insertion direction, and an array of terminal-to-terminal areas between the connector terminals disposed in a first column, and terminal-to-terminal areas between the connector terminals disposed in a second column are shifted from each other in a column direction. If a further different expression is made to the zigzag layout, then the plurality of connector terminals have an array of two columns formed back and forth as viewed in an IC card insertion direction, and a column-direction layout of the connector terminals disposed in a first column and a column-direction layout of the connector terminals disposed in a second column are shifted from each other in a column direction.
Owing to the adoption of a plural-column layout corresponding to a form typified by the zigzag fashion in an array of the connector terminals, a relatively simple structure can be adopted in a card slot, wherein a large number of slot terminals thereof are alternately disposed in parallel while the amounts of protrusion thereof are being changed. A connector terminal array of a downward IC card is adopted in a specific connector terminal array of the IC card as it is. On the other hand, if a function dedicated to an upward IC card is assigned to another zigzag connector terminal array, then such downward compatibility that the upward IC card is made available by being mounted in a card slot of the downward IC card, can be also realized.
In terms of the function expansion of the IC card, the connector terminals of the card include a first connector terminal connected and dedicated to the first functional block, a second connector terminal connected and dedicated to the second functional block, and a third connector terminal sharing an operating power supply commonly to both the first functional block and the second functional block. By dedicating data terminals or the like other than a power supply to the first functional block and the second functional block respectively, the implementation of the upward compatibility and downward compatibility are facilitated.
When one attempts to achieve compatibility between three generations or IC cards of three types or more, such a case that a connector terminal array of a first IC card is adopted for a connector terminal column corresponding to a first column as it is, whereas a dedicated function added to a second IC card is assigned to a connector terminal column corresponding to another zigzag second column, and dedicated functions added to a third IC card are assigned to both the specific terminal column corresponding to the first column and the connector terminal column corresponding to the second column, is assumed. At this time, the implementation of upward compatibility and downward compatibility between the second IC card and the third IC card is taken into consideration. To this end, a structure is adopted in which the connector terminal at one end extending in a column direction of the connector terminals disposed in the second column extends to a position where the connector terminal adjoins, in a column direction, the connector terminal disposed in the first column and placed at one end extending in a column direction of the connector terminals thereof, and the connector terminal at the other end extending in a column direction of the connector terminals disposed in the second column extends to a position where the connector terminal adjoins, in a column direction, the connector terminal disposed in the first column and placed at the other end extending in a column direction of the connector terminals thereof. According to it, such compatibility that the first to third IC cards are mutually inserted even in a slot of any of other IC cards and made available, can be easily realized.
[2] The function expansion of the IC card is intended for a multibank memory, for example. At this time, the first functional block is a first memory card unit including an electrically rewritable first non-volatile memory, and a first controller which performs access control on the first non-volatile memory in accordance with instructions supplied from the first connector terminal and control on an interface with the outside via the first connector terminal. The second functional block is a second memory card unit including an electrically rewritable second non-volatile memory, and a second controller which performs access control on the second non-volatile memory in accordance with instructions supplied from the second connector terminal and control on an interface with the outside via the second connector terminal.
If the multimedia card or the like placed under the present situation is taken into consideration although a specific function of each connector terminal is arbitrary, then the first connector terminal includes a clock terminal and a data terminal, the second connector terminal includes a clock terminal and a data terminal, and the third connector terminal includes a source voltage supply terminal and a ground voltage supply terminal.
The first memory card unit and the second memory card unit are configured as a parallel operable multibank memory unit.
In order to increase security of data stored in each nonvolatile memory, the first controller may have a security function for encrypting data written into the first non-volatile memory and decrypting data read from the first non-volatile memory or effecting other encryption on the data, and the second controller may have a security function for encrypting data written into the second non-volatile memory and decrypting data read from the second non-volatile memory or effecting other encryption on the data.
[3] The function expansion of the IC card is intended for a multifunction. At this time, the first functional block is a first data processing unit provided with a first non-volatile memory, and a first controller which performs access control on the first non-volatile memory and performs control on an interface with the outside via the first connector terminal. The second functional block is a second data processing unit provided with a second non-volatile memory, and a second controller which performs access control on the second non-volatile memory and performs control on an interface with the outside via the second connector terminal. The first data processing unit and the second data processing unit respectively have areas for storing secrete codes for security, separately.
Thus, one IC card is capable of realizing multifunction facilities different in security level.
The first data processing unit makes possible even writing of a secrete code into a secrete code storage area at a non-volatile memory manufacturing stage. The second data processing unit makes possible even writing of a secrete code into a secrete code storage area at a manufacturing stage of the IC card. Thus, the setting of the secrete code is made possible by a method or a procedure necessary to maintain security, according to the difference in security level. When, for example, the first data processing unit is set as a memory card unit of a general data storage application, and the second data processing unit is set as a microcomputerized SIM card unit, the security for the second data processing unit for processing/managing account information must be unavoidably kept strict as compared with the first data processing unit, thus making it possible to meet such a demand sufficiently.
Even when the first data processing unit is configured as the memory card unit of the general data storage application, the first controller may preferably adopt a security function for encrypting data written into the first non-volatile memory and decrypting data read from the first non-volatile memory or effecting other encryption on the data with a view toward enhancing effectivity of copyright protection or the like of data stored in the memory card unit.
When the memory card unit and the SIM card unit or the like are adopted as the multifunction facilities, e.g., the first connector terminal includes a clock terminal, data terminals of plural bits and a command terminal of one bit, the second connector terminal includes a clock terminal, a data terminal and a reset terminal, and the third connector terminal includes a source voltage supply terminal and a ground voltage supply terminal.
[4] When a connector terminal for source voltage supply is disposed in a connector terminal column corresponding to a first column as viewed in an IC card insertion direction, a connector terminal column corresponding to a second column is formed with a terminal-to-terminal area at a position adjacent to the source voltage supply connector terminal. If other connector terminals adjacent to the source voltage supply connector terminal are disposed in the connector terminal column corresponding to the second column in a zigzag form, there is a possibility that slot terminals of a card slot corresponding to the other connector terminals will contact both a source supply connector terminal and other connector terminals located ahead of the other connector terminals in the course of the insertion of an IC card into the card slot before the slot terminals contact the other connector terminals. If a power-supply or source slot terminal is already brought into contact with the source voltage supply connector terminal in this state, there is then the fear of a power-to-power short. If a structure for ensuring the terminal-to-terminal area is adopted, then means for increasing the distance between the connector terminal columns corresponding to the first and second columns and narrowing the width of each connector terminal may not be taken.